For example, in ducts or the like, foam molded articles are widely used in which plate-shaped parts such as flanges are connected to a tube body.
In particular, in ducts used for delivering air from an air-conditioner, when tube-shaped foam molded articles are employed, lightweight ducts having a satisfactory thermal insulation property can be realized. Further, in such ducts, when the foaming magnification at the time of molding is increased so that air bubbles in the inside of the foam article are increased, thermal insulation property and the weight reduction can be improved. Thus, such a configuration is more effective.
For example, foam molded articles of this kind are molded by mold clamping of foamed resin in a molten state by using split metallic molds. In recent years, in association with improvement in molding techniques, mass production of foam molded articles with an increased foaming magnification is becoming achievable.
Further, Patent Document 1 (Japanese Patent Laid-open Publication No. 2011-131776) which is a technical literature filed by the present applicant discloses a technique that two resin sheets having different foaming magnifications to each other are mold-clamped by split metallic molds so that a foam molded article having a tube body and a plate-shaped part is molded.